Download Astronomy 111 - Lecture 1

Astronomy 111 - Lecture 1
Introducing the Scientific Method
and
Specifics of Astronomy within it
Definitions
• Science (n) :
(Webster’s New Universal Unabridged Dictionary, 1996)
– a branch of knowledge or study dealing with a body of facts or truths systematically
arranged and showing the operation of general laws
– a systematic knowledge of the physical or material world gained through observation
and experimentation
– any of the branches of natural or physical sciences
– systemized knowledge in general
– knowledge, as of facts or principles, gained by systematic study
– a particular branch of knowledge
– skill, esp. a precise application of facts or principles; proficiency
• 1300-1350; ME<MF<L scientia ; scire to know
Definitions
• Scientific method (n) : (same source)
–
–
–
–
–
a method of research in which
a problem is identified
relevant data are gathered
a hypothesis is formulated
and the hypothesis is empirically tested.
• 1850-1855 !
The Scientific Method at work
The Scientific Method
• Common misconception :
– Science cannot prove that hypothesis is ‘true’ !
– Only assertion that ‘nothing proved it wrong so far’  Inherent skepticism and
open-ness of science
– NOT a weakness, rather a strength (‘not knowing everything with certainty’ does
not mean ‘not knowing anything’ !)
• Scientific hypothesis must be falsifiable (at least principally)
Definitions
• Astronomy (n) : (same source)
– the science that deals with the material universe beyond the Earth’s
atmosphere
– Gk : astron – star
– Gk : nomos – a system of laws
• cf. eco-nomy, taxo-nomy
• NOT Astro-logy !!!
Astronomy as a Science
• Today "Astronomy" synonymous with "Astrophysics", the study
of the physics of celestial objects; the solar system and its
constituents, the properties, birth, life and death of stars,
interstellar gas and dust, galaxies and clusters of galaxies, and
finally the study of the Universe as a whole ("Cosmology").
Astronomy as a Science
• Complication : Objects of scientific interest out of reach (mostly) !
• 3 Main Questions about Phenomena :
– What is it ?
• How bright ? What colour ? How far away ? What material ? ....
– How does it work ?
• Underlying physiscs  Theories
– How does it evolve ?
• How did it form, how will it develop over time?